Addiction is a disorder of the brain’s reward system which arises through transcriptional and geneticist mechanisms and occurs over time from chronically high levels of exposure to an addictive stimulus (e.g., morphine, cocaine, sexual intercourse, gambling, etc.).Protein FosB, a gene transcription factor, is a critical component and common factor in the development of virtually all forms of behavioral and drug addictions.Two decades of research into Protein FosB’s role in addiction have demonstrated that addiction arises, and the associated compulsive behavior intensifies or attenuates, along with the over expression of Protein FosB in the D1-type medium spiny neurons of the nucleus encumbers. Due to the causal relationship between ProteinFosB expression and addictions, it is used clinically as an addiction bio marker. Protein FosB expression in these neurons directly and positively regulates drug self-administration and reward sensitization through positive reinforcement, while decreasing sensitivity to aversion.
As described by two groups of researchers, addiction exacts an “astoundingly high financial and human toll” on individuals and society as a whole through the direct adverse effects of drugs, associated healthcare costs, long-term complications (e.g., lung cancer with smoking tobacco, liver cirrhosis with drinking alcohol, or meth mouth from intravenous methamphetamine), the functional consequences of altered neural plasticity in the brain, and the consequent loss of productivity. Classic hallmarks of addiction include impaired control over substances or behavior, preoccupation with substance or behavior, and continued use despite consequences. Habits and patterns associated with addiction are typically characterized by immediate gratification (short-term reward), coupled with delayed deleterious effects (long-term costs).
Examples of drug and behavioral addictions include: alcoholism, amphetamine addiction, cocaine addiction, nicotine addiction, opiate addiction, food addiction, gambling addiction, and sexual addiction. The only behavioral addiction recognized by the DSM-5 is gambling addiction. The term addiction is misused frequently to refer to other compulsive behaviors or disorders, particularly dependence, in news media.An important distinction between drug addiction and dependence is that drug dependence is a disorder in which cessation of drug use results in an unpleasant state of withdrawal, which can lead to further drug use. Addiction is the compulsive use of a substance or performance of a behavior that is independent of withdrawal.